Ice cube maker



Aug. 12,v 195s R. GA'LIN 2,846,854

ica CUBE MAKER v 3 Sheets-Sheet 1 Filed Feb. 18, 1954 INVlgNIoR. Robert Galln His Attorney Aug. 12, 1958 R. GALIN I 2,845,854

ICE CUBE MAKER Filed Feb. 1s. 1954 s sheets-sheet 2 INVENTOR. Robert Golm His Attorney United States Patent O ICE CUBE MAKER Robert Galin, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich., a vcorporation of Delaware Application February 18, 1954, Serial No. 411,160

4 Claims. (Cl. 62.-233) This invention relates to refrigerating apparatus and more particularly .to an ice maker.

It is an object of this invention to provide an automatic ice .maker in which the ice maker mechanism is small .enough in size that it may be used within a home refrigerator .or the like.

Another object of this invention is to provide an automatic ice maker in which the ice cubes freeze rapidly and in which no heating is required for releasing the ice cubes from the'freezing trays.

Still another `object of this invention is to provide an ice cube maker which dispenses the cubes in dry condition so .as to prevent the cubes vfrom freezing together in the storage tray. The above and other objects are accomplished by rotatably supporting an ice ltray in direct heat transfer relationship with a stationary cylindrical evaporator. The ice is removed ,from {betr-ay :by tilting and distorting the tray or the tray grid withont removing the tray from its support yand without applying any heat to the tray.

Further objects and advantages of the `present invention will be apparent from the following desription, reference being had to the accompanying drawings, wherein a preferred form of the present invewon is clearly shown.

In the drawings:

Figure l is a front elevational view rshowing the preferred embodiment of the invention installed in a home refrigerator;

Figure 2 is an elevational view with parts broken away and partly diagrammatic showing the preferred embodiment of the invention;

VFigure 3 is a plan view of the ice making mechanism with parts broken away showing the ice tray .and ice tray Vtil-ting mechanism;

Figure .4 is a sectional view taken substantially on line 4-4 of Figure 2 showing a part of the stationary frame broken away;

Figure 5 is :a fragmentary sectional view taken substantially on line 5 5 of Figure 2 showing the device in the ice cube releasing process;

Figure 6 is a schematic circuit diagram showing the electrical controls; and

Figure 7 is a perspective view of a slightly modified type of ice maker.

Referring now to the Figure 1 of the drawing wherein a preferred yembodiment oflthe invention vhas been shown, reference numeral 10 generally designates a conventional refrigerator cabinet having a frozen food storage cornpartment 12 and an unfrozen food storage compartment 14 which are adapted to be refrigerated by means of a conventional refrigeration system to be described more fully hereinafter.

The ice making apparatus comprises an ice maker u nit generally designated by the reference numeral 16 which is adapted to be mounted in the frozen food storage compartmentslZ and a water supply unit 18 adapted to be Patented Aug. 12, 1958 mounted in the unfrozen food storage compartment 14. The water in the unit 18 is then precooled to a temperature slightly above freezing before it is supplied to the ice cube maker 16. The unit 18 may be manually lled or it -rnay b e connected to :a source of water under pressure such as a city water supply system.

The ice maker unit 16 consists of a fixed cylindrical evaporator assembly generally designated by the reference character 20. The evaporator assembly serves to refrigerate a rotatable cylindrical tray support 22. The .tray support 22 is a cast aluminum element having a flat tray supporting surface 24 formed on its one side. A waxed aluminum ice tray 26 is supported on the flat surface 24 in the manner illustrated so as to be in direct thermal exchange relationship with the surface 24 at all times. A exible grid element 28 which is used in releasing the ice cubes from the tray cooperates with the tray 26 so as to form a plurality of ice cube forming pockets 30. After the ice cubes have been frozen in the tray, the support 22v is rotated approximately 1009 at which time the grid 28 is mechanically separated lfrom the tray and is twisted so as to release the ice cubes in la manner to be described more fully hereinafter. The

rotatable support 22 has a drive gear 32 secured ,to tis one end and Ythis drive gear meshes with a pinion 34 driven by an electric motor 36 so as to canse rotation of the support 22.

The evaporator `assembly 20 is carried by a pair of brackets 5l) which rest on the -bottom wall 54 of the frozen food storage compartment 12, In order to provide sucient transfer of heat between the liquid refriger.- ant supplied to the evaporator 20 and the water to be frozen, the evaporator 20 -is provided with inner and .outer cylindrical shells 56 and 58 respectively which are held between a pair of fixed end members 6l) and 62 carried by the brackets 50 and V51 as best shown in Figure 2. The interior of the inner shell 56 forms an accumulator chamber 68 which communicates with the surrounding chamber by means of aperturesll). The liquid refrigerant is supplied to one end of the space .63 between the inner `and outer shells through a liquid supply passage 64 provided adjacent the ,one end of the evaporator. The vaporized refrigerant leaves .the inner charnber 68 through the passage 172,

A spirallyV wound wire mesh type of tubing 59 has been inserted between the inner and `outer cylindrical .elements 5 6 and ,58 so as to cause the incoming liquid refrigerant to travel from the one end of the evaporator to the other end thereof in a spiral direction. The wir-.e mesh of the `tubing helps to feed liquid refrigerant ,upf wardly by capillary action into. contact with the entire outer shell 58 when there is not enough liquid refrigen antbeing supplied .to the evaporator 2.0 to keep it 'filled with liquid refrigerant. After the refrigerant has traveled the full lengthy of .the evaporator chamber 63 it will ow into the chamber 6.8 through the apertures 7 0. The chamber 68 serves as a disengaging chamber and an accumulator for the unvaporized liquid refrigerant which enters the chamber 68. The vaporized refrigerant leaves the chamber 68 lvthrough the outlet passage 72 formed in thoupper Portion .ofthe Stationary ond member .6.0,

It will be noted that a small clearance space yl, has boon provided between .the .oil-ter surface of the ototionarv Cylindrical element .5.8 and. the rotatable .cylindrioal .element 22.. This space is preferably llod with a liquid Silicone Wllioh .facilitates the transfer of heat from the member@ .to .the evaporator lo order to prei/.oat 'the escape of .Silicone .from the .clearance 74.. .O-,rioa seals 7.6 have been provided at the ends of the elements 20 and 22. These O-rings then serve as bearings for the rotatable portion of the device.

Any suitable refrigerant liquefying means could be used for supplying liquid refrigerant to the evaporator assembly 20. Preferably, however, the liquid refrigerant is supplied to the evaporator from the main refrigeration system which cools the food compartments 12 and 14. A preferred refrigeration circuit has been shown diagrammatically in Figure 2 `of the drawing and includes a standard motor-compressor unit 81) which discharges compressed refrigerant into a standard condenser 82 which serves as a condenser for all of the refrigerant used in the system. The condensed refrigerant flows into a combination receiver and drier receptacle 84 from whence a portion ofl liquefied refrigerant is supplied through a capillary tube type lof restrictol 85 into the ice cube freezing evaporator 20. Another portion of the liquid refrigerant is caused to flow through a restrictor 86 into the evaporator 88 which refrigerates the frozen food compartment 12. The amount of liquid refrigerant supplied to the evaporator 88 is sufficient so that a portion of liquid refrigerant overflows into a plate type evaporator 90 mounted in the food storage compartment 14. The vaporized refrigerant returns to the motor-compressor unit 80 through the suction lines 92 and 93 as shown.

The refrigeration system which has diagrammatically been shown in Figure 2 is intended to represent a conventional refrigeration system except for that portion which connects to the ice maker. It is contemplated that the usual thermostatic controls would he provided for controlling the operation of the motor-compressor -unit and since these controls are well known and may be varied considerably without departing from the spirit of the invention the same will not be described. For a dis* closure of a control system which may be used, reference is hereby made to copending application Serial No. 272,962 tiled February 23, 1952, now Patent No. 2,672,023 of March 16, 1954.

For quick freezing of the ice cubes it is important that the aluminum ice tray be held in good thermal exchange relationship with the refrigerated surface 24. To accomplish this the tray is provided with anchoring lugs 100 secured thereto at its four corners to which hold down springs 102 are attached. The coil springs 102 have their upper ends secured to the anchoring lugs 100- and their lower ends secured to projections 104 formed on the rotatable cylindrical element 22 and thus the springs serve to press the tray firmly into contact with the upper at tray supporting surface 24. The trays may -be removed for cleaning by unhooking the springs.

The plastic grid 28 has its one edge riveted to the projecting ends of the anchoring lugs 106 as indicated at 106 (see Figures 3, 4 and 5) whereby the one edge of the plastic grid cannot be moved relatively to the adjacent edge of the aluminum tray 26. The other edge of the grid is yieldably held down relatively to the tray by means of two springs 108 located at the two leading corners -of the tray. By virtue of the above described construction the grid 26 is yieldably held down in the tray 26. As best shown in Figures 2 and 3 of the drawing, the grid includes longitudinally extending center strip 110 and a plurality of transversely extending divider elements 112 which form cells which are open at the top, bottom and ends. The grid is constructed in this manner so that the water to be frozen is in direct thermal exchange relationship with the bottom, ends and sides of the aluminum tray 26.

When the water has been properly frozen into cubes, the motor 36 rotates the member 22 and the tray supported thereon from the position in which it is shown in Figures 2, 3 and 4 to the position in which it is shown in Figure 5. As the motor 36 rotates the assembly the one leading corner of the grid strikes a stop 114 which is provided on the frame member 51 with the result that the plastic grid begins to flex as the motor continues to rotate the element 22 and the associated tray 26. Upon l continued rotation, the other leading corner of the grid strikes the stop 116 provided on the stationary frame member 50. lt will be noted that the stops 114 and 116 are oiset from one another so as to produce a progressive warping of the grid. Since the trailing edge of the grid is rigidly secured to the tray 26 which is rmly held in place against the fiat surface 24, the grid is progressively warped with the result that the ice cubes are released and fall into the tray 118 which is arranged to receive the ice cubes as they are released from the grid. Suitable timing mechanism which will be described more fully hereinafter serves to reverse the direction of rotation of the motor 36 after the ice cubes have all been released so as to return the ice tray to the position in which it is shown in Figures 2, 3 and 4. Stops 151 and 153 are provided on the drive gear 32 and engage the edges of the frame to limit the oscillation of the element 22. The motor stalls between the time one of the stops strikes the frame and the time the timing mechanism deenergizes the motor. The ice tray is refilled with water from a water tank 18 after the tray is returned to its upright position. By virtue of the fact that the water` receptacle 18 is mounted in the compartment 14, the water supplied to the ice tray will have been precooled with the result that it will not take long for the water to freeze. A water pump 120 is used for pumping the water from the tank 18 up into the tray. The water pump 120 is driven by an electric motor 122 which is periodically energized by timing mechanism to be described more fully hereinafter. The water is preferably pumped into the tray at a slow rate so as to allow the water to ow from the one ice cube compartment into which it is discharged into the other ice cube compartments merely by leakage past the various partitions of the grid 28.

Referring now to Figure 6 of the drawing wherein the electrical controls have been shown, reference numeral designates the power lines which are used for supplying electrical power to the controls. Reference numeral 132 designates a conventional timer motor which is connected across the power lines through a switch 134 which may be used for stopping the timer. The switch 134 is adapted to be controlled by means of a solenoid 136 which in turn is controlled by means of a pair of switches 137 and 138.

The switch 137 is a weight operated switch which is adapted to be mounted under the ice cube receiving receptacle 18. This switch is opened in response to a predetermined accumulation of ice cubes in the pan 118 indicating that the pan is full of ice cubes and that no more ice cubes should be frozen. The switch 138 is a float operated switch which is adapted to be opened when the supply of water in the water receptacle 18 has been exhausted. Thus the ice making pro-cess would be discontinued in the event that the ice cube receptacle 118 has been filled or the supply of water in the receptacle 18 has been exhausted. The timer motor 132 operates a first switch 140 which controls the pump motor 122 as shown so as to operate the motor pump 120 for the required length of time at the beginning of each ice freezing cycle. The timer motor also operates a switch 142 which is arranged in series with the reversible motor 36. The motor 36 is of the well known type which is adapted to have its direction of rotation reversed each time the motor is energized. For purposes of illustration, the motor has been shown as having a pair of direction reversed shading poles 144 and 148 controlled by a switch also operated by the timer motor in such a manner that each time the timer motor closes the switch 142, the switch 150 will close the circuit to a different one of ythe shading poles.

One of the big problems in automatically operated ice makers which are adapted to be mounted in the freezing compartment of a refrigerator is that of preventing excessive accumulation of frost on the cold parts and particularly .the gear mechanism. As shown in Figure 2 of the drawing, van insulating gasket 15,0 is provided lbetween the ylarge drivin-g gear 32 and the tray supporting .element 22 s o as to reduce vto a minimum the transfer of heat between the Vgea-r 32 andthe member 22. Insulating gaskets 152 are also provided between the end pieces 60 and 62 of the evaporator assembly 20 and the mounting brackets 50 and 51. Furthermore, the electric motor 36 is supported in spaced relationship to any of the refrigerated surfaces in the freezer compartment so as to reduce .to a minimum the transfer of heat by conduction to the electrical motor.

In the event that any of the silicone should escape from the space between the rotatable cylindrical element 22 and the stationary cylindrical evaporator 20 a filler plug 160 has been provided in the one end piece 62 and a similar vent plug 164 has been provided in the end piece 60. The vent plug 164 may be removed when adding silicone s-o as to allow any air which may have entered the silicone chamber to escape when new silicone is being added. Upon having supplied the required quantity of silicone to the space, the plugs 160 and 164 are replaced.

In Figure 7 of the drawing there is shown a slightly modied ice maker which differs from the ice maker shown in Figures 1 to 6 only in the construction and arrangement of the ice tray and ice releasing mechanism as described hereafter. As shown in Figure 7, a stationary cylindrical evaporator assembly 200 which is constructed like `the evaporator assembly 20 shown in the other figures of the drawing is used to refrigerate a rotatable tray support 202. The rotatable tray support 202 differs slightly from the .tray supports shown in the other figures of the drawing in that it supports a pair of trays 204 and 206 on opposite sides thereof. These trays are made of `sheet metal, preferably aluminum with a wax coating, and are held against the opposed refrigerated at surfaces 208 by means of coil springs 210 located at the four corners of the trays as shown. A motor 212 which is provided with a pinion 214 drives the gear 216 which is attached to the member 102 in the same manner as the gear 32 is attached to the member 20. The evaporator 200 is adapted to be supplied with refrigerant in the same manner as the evaporator 20 sho-wn in the other figures of the drawing. Likewise the motor 212 is adapted to be controlled in the same manner as the corresponding motor 36 shown in the other figures of the drawing. One of the principal differences between the modification shown in Figure 7 and the device shown in Figures 1 through 6 is that the ice freezing trays are not provided with a exible grid which form ice cubes with the result that the ice freezes in the trays in the shape of a large slab. The slabs are released from the trays by inverting the trays and then distorting the tray while in the inverted position. The distortion is accomplished by providing a projection 220 on the tray 206 and the projection 222 on the tray 204 and having these projections engage stops 224v and 226 respectively carried by the stationary frame members 228 and 230 respectively as the respective trays are inverted. Thus when the tray 206 is inverted and the projection 220 provided on the tray strikes the stationary stop 224 it causes the one corner of the tray to stop while the rest of the tray continues to move a predetermined distance. This distorts the tray in the manner shown in Figure 7 and the slab of ice is thus released from the tray and falls onto a cutting grid 232 which has heated crosswires 234 arranged as shown. As the slab of ice strikes the crosswires 234 the will tend to melt the ice along the lines of contact with the ice and cut the slab into squares or cubes which then drip down into the repetacle 240 which corresponds to the receptacle 118 shown in Figures 1 and 2.

The same type of control circuit as shown in Figure 6 is used for controlling the ice maker shown in Figure` 7. The ice maker of Figure 7 is preferably mounted in the unfrozen food compartment of the evaporator so that the ice cubes which are 4frorned by cutting a slab of ice by means of electrically heated wires will not freeze together. The iceeubes vformed bythe device shown ill Figures 1 through y5 .are ,dry .when released from the ice Atrav and ,consequently do ,not freeze together in the ice Cube .Storage tray 1.18..

While the form of embodiment ofthe invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted, as may come within the scope of the claims which follow.

What is claimed is as follows:

1. In an ice maker for use in .a refrigerator, a cylindrical evaporator, a cylindrical ice tray support telescoped over said cylindrical evaporator, an ice tray carried by said support and a liquid heat transfer medium between said evaporator and said tray support, spaced O-ring means on said cylindrical evaporator serving as a bearing support for said ice tray support and preventing the escape of said liquid heat transfer medium from the space between said evaporator and said tray support, a motor for rotating said ice tray support relative to said evaporator for dumping ice from said tray, and means for periodically stopping said motor and for reversing the direction of rotation of said motor.

2. In an ice maker, means forming a cylindrical evaporator, a cylindrical ice tray support telescoped over said cylindrical evaporator, a drive gear secured to said cylindrical support, insulating means between said drive gear and said support, a motor having a pinion arranged in driving engagement with said drive gear, supporting means for said motor and said cylindrical evaporator, and insulation between said evaporator and said supporting means.

3. In an ice maker for use in a refrigerator, a cylindrical evaporator, a cylindrical ice tray support telescoped over said cylindrical evaporator and journalled thereon, O ring gasket means on said cylindrical evaporator between said cylindrical evaporator and said tray support adjacent the opposite ends thereof and cooperating with said evaporator and said support to form a' closed cavity for receiving a permanent charge of a liquid heat transfer medium, a permanent charge of a liquid heat transfer medium between said evaporator and said tray support, `and means for rotating said tray support on said cylindrical evaporator, said 0 ring gasket means comprising the sole means for supporting said tray support on said evaporator.

4. In an ice maker, a cylindrical evaporator, a cylindrical ice tray support mounted on said cylindrical evaporator and journalled thereon, a liquid heat transfer medium between said evaporator and said tray support, and O ring bearing means between said evaporator and said tray support for confining said heat transfer medium and serving as the sole bearing support for said ice tray support.

References Cited in the file of this patent UNITED STATES PATENTS 1,279,608 Summers Sept. 24, 1918 1,980,571 Brach Nov. 13, 1934 2,161,321 Smith June 6, 1939 2,259,066 Gaston Oct. 14, 1941 2,297,371 Siedle Sept. 29, 1942 2,364,559 Storer Dec. 5, 1944 2,403,275 Gilliam July 2, 1946 2,403,406 Smith July 2, 1946 2,407,058 Clum Sept. 3, 1946 2,471,655 Rundell May 31, 1949 2,493,900 Schaberg Ian. 10, 1950 2,526,262 Munshower Oct. 17, 1950 (Other refer-ences on following page) UNITED STATES PATENTS Russell Mar. 20, 1951 Erickson July 3, 1951 Munshower Sept. 25, 1951 Knowles Nov. 4, 1952 5 8 Ayres June 29, 1954 Comstock Dec. 28, 1954 Andersson Sept. 13, 1955 Ashby Sept. 13, 1955 Sampson Aug. 7, 1956 

